Global Patent Index - EP 0615079 A1

EP 0615079 A1 19940914 - Ratio control valve for a continuously variable transmission.

Title (en)

Ratio control valve for a continuously variable transmission.

Title (de)

Schaltsteuerventil für ein stufenlos verstellbares Getriebe.

Title (fr)

Soupape de contrÔle de sélection des vitesses d'une transmission à variation de vitesse continue.

Publication

EP 0615079 A1 19940914 (EN)

Application

EP 94300741 A 19940201

Priority

US 2799893 A 19930308

Abstract (en)

A continuously variable transmission control system having adjustable driving and driven sheave assemblies (124,126) connected drivably by a torque transfer belt or chain (144), each sheave assembly having a fluid pressure operated servo with a pressure chamber, distribution of control pressure to one servo (150,158,162) effecting a transmission ratio adjustment, control of pressure distribution to the other servo (202,210) resulting in a clamping force, a ratio control valve (246) for controlling distribution of pressure to the ratio controlling servo to effect upshifts and downshifts, provision being made for stabilizing the ratio control valve by providing for flow entry to the ratio control valve that is unrestricted, flow distribution to the ratio controlling servo having a controlled restriction whereby stability of the ratio control valve is achieved, fluid displaced from the ratio controlling servo being adapted to circulate through the ratio control valve to the inlet side (372) of the control system pump (70,72). <IMAGE> <IMAGE> <IMAGE>

IPC 1-7

F16H 61/00; F04C 15/02; F04F 5/54

IPC 8 full level

F04F 5/54 (2006.01); F16H 61/662 (2006.01)

CPC (source: EP US)

F04F 5/54 (2013.01 - EP US); F16H 61/66259 (2013.01 - EP US); F16H 57/0438 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0615079 A1 19940914; EP 0615079 B1 19970910; DE 69405429 D1 19971016; DE 69405429 T2 19980129; US 5383812 A 19950124

DOCDB simple family (application)

EP 94300741 A 19940201; DE 69405429 T 19940201; US 2799893 A 19930308